NA TURE 



409 



THURSDAY, SEPTEMBER 3, 1908. 



MARINE DEPOSITS. 

 /.(■.? Ddpots marins. By Dr. L6on W. Collet. Pp. 

 vii + 325; with 35 figures in text and a map. (Paris : 

 Octave Dion, igo8.) Price 5 francs. 



THE publication of this volume is connected with 

 the inauguration of a scientific work on the 

 grandest scale. It is proposed to issue under the 

 title of " Encyclopddie scientifique " about 1000 

 volumes in the French language, dealing with every 

 branch of pure and applied science. The general 

 director of this vast work is Dr. Toulouse, and its 

 general secretary M. H. Pieron ; but for each of the 

 branches of science, to the number of forty, an editor 

 specially conversant with the subject has been 

 secured. 



The volume before us is the first published of the 

 group of works on " Oceanographie physique," the 

 editor of which is Dr. Jules Richard, of the Mus^e 

 Oc^>anographique de Monaco. Dr. Collet, who is a 

 privat-docent in the University of Geneva, had the 

 advantage of spending two years of study in the 

 Challenger Office in Edinburgh, and the volume is 

 appropriately dedicated to Sir John Murray. The 

 work is professedly based on Murray and Renard's 

 well-known Challenger volume, though a considerable 

 amount of information obtained by later researches 

 is incorporated by the author. The illustrations are 

 taken either from the Challenger Report, from Dr. 

 J. M. Flint's Bulletin on the Oceanography of the 

 Pacific, from the Encyclopaedia Britannica, or from 

 the papers published by the author and Dr. Lee on 

 glauconite deposits. 



The book commences with a slight sketch of the 

 work done in the subject before the despatch of the 

 Challenger Expedition, and an essay on the effects of 

 temperature in determining the distribution of plants 

 and animals at the surface and in the deeper parts of 

 the ocean. The classification adopted for the various 

 deposits is that of Sir John Murray, with some slight 

 and unimportant modifications, though the author 

 notices the attempt of Thoulet to substitute for this 

 grouping one on a mathematical basis — the size and 

 chemical composition of the particles of which the 

 deposits are built up being taken as a guide. 



While the accounts of the several oozes and of the 

 manganese nodules and other materials found in the 

 red muds are condensed from the descriptions in the 

 Challenger volume, the chapter on the glauconite 

 deposits extends to much greater length (48 pages), 

 and is taken, with its illustrations, from the paper 

 published by the author and Dr. Lee in the Proceed- 

 ings of the Royal Society of Edinburgh. 



The fourth division of the book, dealing with the 

 deposits of coral-origin, extends to considerable length, 

 and includes references to recent works, such as the 

 Funafuti Report of the Royal Society, and the results 

 of Mr. Stanley Gardiner's work in the Indian Ocean. 

 The author adopts the estimate of the last-mentioned 

 naturalist as to the limit of depth of coral-reef build- 

 ing organisms — namely, 64 metres for corals, and 120 

 NO. 2027, VOL. 78] 



metres for " nuliipores." In discussing theoretical 

 conclusions from the known facts concerning coral- 

 reefs, however, the author seems to be labouring 

 under some unfortunate misconceptions. He says : — • 



" Le sondage dc I'atoll dc Funafuti dans les 

 lies de I'EUice fut entrepris aux fins d'obtenir des 

 renseignements sur le soubassement d'une ile coral- 

 lienne; bien que ce but n'ait pas ei& atteint, ce 

 sondage n'en est pas moins tr^s important, comme 

 nous le verrons dans la suit" (pp. 261, 262). 



It cannot, however, be sufficiently understood 

 and remembered that the Coral-Reef Committee 

 of the Royal Society was formed, not to seek 

 for confirmation of any particular theory, but 

 to obtain facts w^hicfi might enable us to 

 put the several theories to a critical test, and in this 

 it was entirely successful. The committee included 

 the advocates of all the different theories, and the plan 

 and details of the expedition were agreed upon by 

 mutual arrangement. The selection of Funafuti— as 

 the most typical of atolls— was made by the late 

 Admiral Sir W. Wharton (who was not a believer in 

 Darwin's theory), and was accepted by every member 

 of the committee. It was agreed by all that a boring 

 of 1000 feet would be sufiicient to test the several 

 theories, even on the most liberal estimate of the 

 depth at which reef-forming corals, &c., could flourish. 

 The actual depth reached was 11 14 feet, and the very 

 careful study of the materials brought up was shown 

 by Dr. Hinde to demonstrate, beyond doubt, that — 

 setting aside subsequent chemical changes— the rock, 

 from top to bottom, consists of the same organisms, 

 in the same conditions as respects position of growth 

 and association. Neither in the microscopical charac- 

 ters of the rock nor in its chemical composition was 

 there the smallest indication in the lowest cores 

 brought up of any volcanic, or, indeed, of any non- 

 calcareous rock being approached. It w-as open, of 

 course, to the opponents of Darwin's views to oppose 

 the undertaking of the boring as an adequate test. 

 But it is scarcely fair, now that the test has been 

 applied under their own auspices, to declare that it 

 is of no value. 



The author reproduces an attempted explanation, 

 with modifications by later authors, of the facts ascer- 

 tained at Funafuti. But it must be remembered that 

 these are new views, put forward since the boring 

 was brought to such a successful termination by the 

 skill and energy of Profs. Sollas and David and their 

 assistants. Neither the theory of a talus nor the 

 amended suggestion of the building up of the lower 

 part of the^ atoll by the growth in situ of deep-sea 

 corals, nuliipores, or other organisms, receives the 

 smallest support from the study of the cores brought 

 up. Every unprejudiced observer of the whole course 

 this discussion has taken must be convinced that the 

 Funafuti boring, far from having failed in its object, 

 was carried to a successful and useful conclusion. 



In the final division of the work the author discusses 

 some of the geological formations in the light of the 

 results obtained by deep-sea explorations. In these 

 he generallv follows and summarises the work of M. 

 Cayeux. In his discussion of the origin of the oolites. 



